2006 DTS

[93SixtySpecial]

Hello everyone,

It's been a while since I've been on here because I moved to a Buick for a while. I've realized that I cannot be without my Cadillacs! So, I'm looking at a 2006 DTS. I'm not sure if it's the performance package or not because I haven't seen the VIN quite yet. I have a few questions for the folks on here.

Is it still the 4T80E transmission and if so, is the P0741 code as common on this year or have they resolved that issue? Out of my 12 Cadillacs that I have owned, 6 of them have been the northstar and half of those had the code.

What have they changed, if anything, on the engine?

Is it true there is no longer onboard diagnostics?

Are there any other prevalent issues I should watch for?

Thanks in advance!

[KHE]

The engine is carryover from 2005. No changes that I am aware of.

True - no more onboard diagnostics - that's not good in my opinion but it would not prevent me from buying the car.

P0741 could happen to any Northstar car. I fixed my '97 STS a year and a half ago and it has been fine ever since.

[93SixtySpecial]

What was the cause for the slightly lower HP rating? Not that 8 HP makes a huge difference, but I'm just curious.

Did you do the repair yourself for the P0741? How tough was that to do? I typically do all my own repairs, but I haven't tackled internally on an FWD tranny.

[Cadillac Jim]

The transmission is still the 4T80E. The 4T80E, like all transmissions, is not entirely static, and there are changes occasionally. A big one with regard to the P0741 is that the viscous TCC was replaced by an electrically controlled converter clutch (EC3) in 2004. Model year 2005-2011 4T80E transmissions use the EC3.

I don't know how susceptible a 2005-2011 4T80E is to the dreaded P0741, but I suspect that one reason for the new TCC was to make it more reliable.

One thing you can do for any transmission is to service it once in awhile. The owner's manual says never service the transmission unless you get a message and a code, which never happens unless you abuse or overheat the transmission. But the service life has a horizon of about 100,000 miles, looking at the service recommendations in my 1997 owner's manual. I serviced my 1997 4T80E every 30,000 to 40,000 miles as long as I had the car.

Another big change was the reformulation of Dexron in 2005 (to Dexron VI) to provide far better control of viscosity with temperature, but most importantly to improve clutch life by 230%, or a factor of 2.3:1.

The combination of these tells me that the 2005-2011 4T80E should show a lot less wear than earlier model years.

I would still have the transmission service every once in awhile.

With regard to your other question, the VIN "Y" final drive ratio, 3.11, was used in the 2006 DTS. If the VIN "9" engine was used, that would be the only model that I know of with that combination. When you get the VIN, check the 8th digit and see whether it is a 9 or a Y.

Also, when you get the VIN, run a CarFAX. And, have the car looked at by a mechanic independent of whoever is selling you the car; this will cost about $100 and will include checking the codes, driving the car through an OBD driving cycle, and checking the codes again.

[Texas Jim]

Hello everyone,

It's been a while since I've been on here because I moved to a Buick for a while. I've realized that I cannot be without my Cadillacs! So, I'm looking at a 2006 DTS. I'm not sure if it's the performance package or not because I haven't seen the VIN quite yet. I have a few questions for the folks on here.

Is it still the 4T80E transmission and if so, is the P0741 code as common on this year or have they resolved that issue? Out of my 12 Cadillacs that I have owned, 6 of them have been the northstar and half of those had the code.

What have they changed, if anything, on the engine?

Is it true there is no longer onboard diagnostics?

Are there any other prevalent issues I should watch for?

Thanks in advance!

Cady Guy...

I have had 2 2006 Performance models, with a combined total of over 190,000 miles and now have a 2011 Platinum...

I put 40,000 on the first one before it burned in my garage fire, and had over 150,000 on the 2nd one when I traded it for the 2011.

I am on another forum that deals ONLY with the 2006 thru 2011 and I have never seen a post about the P0741..

That would be one issue I would not worry about at all.

The Performance model will be a VIN "9" car and have 18 inch wheels and Magnetic Ride suspension, along with automatic tilt and telescoping steering wheel, heated steering wheel, heated AND cooled seats, BOSE stereo, lighted vanity mirrors and should come with THREE keys and TWO fobs...Two keys are the regular ones and the 3rd key is the Valet key.

I have really enjoyed all three of the DTS's I have had...

[KHE]

What was the cause for the slightly lower HP rating? Not that 8 HP makes a huge difference, but I'm just curious.

Did you do the repair yourself for the P0741? How tough was that to do? I typically do all my own repairs, but I haven't tackled internally on an FWD tranny.

The lower HP rating was something to do with a government mandate on how the HP was tested.

I repaired the P0741 by swaping the transmission with one that had only 52,000 miles on it. I drove the car for too long with the P0741 issue and the clutches in the torque converter were coming apart and loading the trans with debris. PITA job - I think there is a thread on this board where I posted my progress.

Starting with 2004 or so, they quit using the viscious torque converter and I have not seen a P0741 issue with anything 2004 and newer.